Fatty acids as biomarkers of microalgae.

Microalgae are primary producers of the food chain and hold prominence towards pharmaceutical and nutraceutical applications. Fatty acids (FAs) are one of the primary metabolites of microalgae, which enrich their utility both in the form of food and fuels. Additionally, the vast structural diversity coupled with taxonomic specificity makes these FAs as potential biomarkers. The determination of lipid and fatty acid profiling of 12 different strains of microalgae has been accomplished in this study and further discussed in respect to their chemotaxonomic perspective in microalgae. Palmitic acid (C16:0) and oleic acid (C18:1n9c) were found to be dominant among the members of Cyanophyceae whereas members of Chlorophyceae were rich in palmitic acid (C16:0), oleic acid (C18:1n9c) and linoleic acid (C18:2n6). The application of principal component analysis (PCA) and algorithmic hierarchical clustering (AHC) resulted in the segregation of the studied microalgal strains into 8 different orders belonging to 2 distinct phyla according to their phylogenetic classification. Nutritionally important FAs like eicosapentaenoic acid (EPA, C20:5n3) and docosahexaenoic acid (DHA, C22:6n3) were detected only in Chlorella sp. belonging to Chlorophyceaen family. Differential segregation of microalgae with respect to their fatty acid profile indicated the potential utility of FAs as biomarkers.